Insulting someone on Facebook, wearing a Qatar soccer jersey, drinking wine on a plane — these are all things that could potentially get you arrested in the United Arab Emirates (UAE).

In recent years, millions of tourists and expats have flocked to the country, especially to its luxurious emirate Dubai. But even though the UAE markets itself as an oasis of freedom in the Gulf, it often cracks down on behaviors that foreigners never dreamed could be illegal.

Radha Stirling helps many of these foreigners with her NGO Detained in Dubai. She told Business Insider that foreigners often don't appreciate the risk they are taking when traveling to Dubai.

"People are convicted every day in cases that would be instantly thrown out of a Western court either for lack of evidence, improper procedure, or for just being frivolous," she said.

There have been several high profile cases of Westerners claiming unfair imprisonment in recent years. Here are just a handful of examples.

Laleh Shahravesh, who faced jail for calling her ex-husband's new wife a "horse" on Facebook

Laleh Shahravesh with her daughter and ex-husband.
(Detained in Dubai)

In March, British mother Laleh Shahravresh was arrested for calling her ex-husband's new wife a "horse" in a Facebook comment, according to Detained in Dubai.

Shahravresh made the posts three years ago when she was in London, said the campaigners. But she and her teenage daughter were detained when they flew to the Dubai to attend her former partner's funeral.

Ahmad was locked up in Sharjah, a city that forms part of the greater Dubai metropolitan area. Sharjah has an especially problematic human rights record, according to Detained in Dubai.

When he was allowed to return to the UK in February, he told The Guardian that he was stabbed, punched, and deprived of food and water for days at a time.

"I thought 100% that I was going to die in the UAE," he said.

Andy Neal, who was arrested on charges related to supplying drugs, which he strenuously denies

Andy Neal.
(Detained in Dubai)

British war veteran Andy Neal has been locked up in the UAE on false drug charges since October 2018, according to campaigners.

The former soldier moved to Dubai with his family in 2015 to live as a civilian and run a dog training business.

He was arrested on charges related to supplying drugs, even though drugs were never found in his possession or blood stream, Detained in Dubai said. A witness who supposedly implicated him said they never mentioned Neal, they add.

The father of two was recently moved to a prison in Abu Dhabi where conditions are poor, and he has limited contact with the outside world, the NGO said.

"He has experienced enough trauma in his life; it breaks my heart that this is happening to my son," Neal's mother Sue said about her son who suffers from PTSD.

Ellie Holman, who was detained after drinking a glass of wine on her flight to Dubai

Ellen Holman with her daughter.
(Detained in Dubai)

Dr. Ellie Holman was detained for drinking a glass of wine on an Emirates Airline flight to Dubai in July 2018.

An immigration official asked the Swedish-born dentist if she had consumed alcohol after a disagreement about her visa escalated, activists said. She said she drank a complementary glass of wine on the plane.

The official replied that the possession of alcohol is illegal in the UAE, even if the drink is already in someone's body, according to Detained in Dubai.

Dr. Holman, who lives in the UK, and her four-year-old daughter were put in a cell, which she said was filthy and hot. She claims did not sleep the three days while in the cell for fear of being raped by guards.

Holman was eventually released and returned home to the UK.

"So far this situation has cost me around £30,000 in legal fees, expenses and missed work. My practice is closed. All of our savings are gone," Holman said at the time.

Matthew Hedges, a PhD student who was accused of being a spy

Matthew Hedges.
(Screengrab/BBC)

Matthew Hedges, a British PhD student, was jailed in May 2018 for spying in the UAE when he traveled to the country to research his doctoral thesis on national security.

He was forced to sign a false confession in Arabic, locked up in solitary confinement, and sentenced to life in jail, Detained in Dubai said.